Rambus handler

ABSTRACT

A test handler for automatically testing rambus type semiconductor devices. The rambus type test handler includes a user tray stacker for stacking a plurality of user trays which are loaded with semiconductor device that have been, or will be tested; a device loading portion for picking up the semiconductor devices from the user trays at a supplying position and loading the semiconductor devices onto boats at a loading position; a heating/cooling chamber for heating or cooling the boats according to test requirements by order of boat receipt from device loading portion; a test chamber for connecting the heated or cooled semiconductor devices to test sockets for testing; a recovering chamber for recovering the temperature of the semiconductor devices to a normal degree, while elevating the boats and discharging the boats through an upper end, sequentially, by order of boat receipt from a lower end of the test chamber; a device sorting portion for picking up test-completed semiconductor devices from the boats discharged from the recovering chamber and stacking respective grades of semiconductor devices to correspondingly predetermined areas of a plurality of conveying buffers; and a device unloading portion for stacking the semiconductor devices from the conveying buffers to the user trays corresponding to the respective grades of the semiconductor devices. Further, there are provided a device loading portion, displaceable hand for sorting the semiconductor devices, contact picker assembly of the test chamber, and position guiding portion.

CLAIM OF PRIORITY

[0001] This application makes reference to, incorporates the sameherein, and claims all benefits accruing under 35 U.S.C. §119 from seven(7) applications entitled “HAND OF VARIABLE PITCH”, “APPARATUS ANDMETHOD FOR TESTING SEMI-CONDUCTOR DEVICE OF RAMBUS HANDLER”, “RAMBUSHANDLER”, APPARATUS FOR TESTING SEMI-CONDUCTOR DEVICE OF TEST HANDLERAND METHOD THEREFOR, APPARATUS FOR TESTING SEMI-CONDUCTOR DEVICE OF TESTHANDLER”, “CONTACT PICKER ASSEMBLY FOR TESTHANDLER”, and “RAMBUSHANDLER”, filed with the Korean Industrial Property Office respectivelyon Dec. 6, 1999, Dec. 14, 1999, Feb. 7, 2000, Apr. 14, 2000, Apr. 14,2000, Apr. 14, 2000, and Nov. 10, 2000,and there duly assigned Ser. Nos.55206/1999, 57612/1999, 5642/2000, 19553/2000, 19554/2000, 19555/2000,and 66867/2000, respectively.

BACKGROUND OF THE INVENTION

[0002] 1. Field of the Invention

[0003] The present invention relates to a test handler for testingperformance of electronic components such as Integrated Circuits (IC),semiconductor chips, etc., and more particularly to a test handler, arambus handler, capable of automatically testing Ball Grid Array (BGA)or Chip Size Package (CSP) type semiconductor devices.

[0004] 2. Description of the Related Art

[0005] Generally, complete assemblies of semiconductor devices(hereinafter called devices) are tested for performances. A test handlertests the devices, in a manner that a certain number of devices areconveyed and connected to test heads for testing, and graded, grouped,and stacked according to the test results. Various test handlers aredeveloped for testing the devices of various shapes and types.

[0006] Such test handlers are constructed to test the devices generallyhaving electrodes (so-called leads or pins) protruding from an outersurface of a package.

[0007] Recently, new types of devices of high-integration such as BallGrid Array (BGA) or Chip Size Package (CSP) type devices have beenmass-produced. The BGA or CSP type devices have an area arrayarrangement in which a plurality of electrodes are arranged on a lowersurface of the package. Due to different electrode arrangement of BGA orCSP type devices, in which the electrodes are arranged on the lowersurface of the devices, there is few conventional test handlers whichcould perform the testing operation upon these devices. Accordingly,there is a growing demand for the proper testing device to test the BGAor CSP type devices.

[0008] When testing the devices, also, since the devices have to be indirect contact with sockets of the test heads, it is required thatdevices be employed in the test device to guide and press the devices ata proper pressure.

[0009] In a general test handler, there are different pitches bothbetween user trays for supplying the devices and between devicereceiving sections of device testing boats. Accordingly, for a highertesting efficiency, while picking-and-placing the devices, it isnecessary that the pitches between the devices are adjusted, and furtherthat the picking-and-placing operation includes a process of adsorbing aplurality of devices.

[0010] In order to compensate the pitches between the user trays anddevice receiving sections of the boats, adjusting devices such as apre-sizer, or a link type adjusting device of a hand has been used toadjust the pitches between picking-and-placing cylinders. In order tofurther increase the testing efficiency, the hand usually includes eightpicking-and-placing cylinders and vacuum pads.

[0011] The conventional test handlers, however, have shortcomings asfollows: when using the pre-sizer, device picking-and-placing efficiencycould hardly be good, and when using the link type adjusting device,cumulative errors between the links hinders precise picking-and-placingoperation.

[0012] Further, when the testing time is relatively shorter than thepicking-and-placing time, there occurs cost inefficiency since theheavily invested test device idles.

SUMMARY OF THE INVENTION

[0013] The present invention has been made to overcome theabove-mentioned problems of the related art, and accordingly, it is anobject of the present invention to provide a test handler, i.e., arambus handler capable of automatically testing rambus type devices suchas a Ball Grid Array (BGA) or Chip Size Package (CSP) type devices.

[0014] It is another object of the present invention to provide a rambushandler having an displaceable hand which does not incur cumulativeerror during pitch adjustment between cylinders, and is also capable ofhandling a plurality of devices in one picking-and-placing operation,thus, reducing picking-and-placing time.

[0015] It is still another object of the present invention to provide arambus handler having a means capable of picking and connecting thedevices into test sockets in a stable and accurate manner when pickingthe devices from test chambers for testing.

[0016] The above objects are accomplished by a rambus handler accordingto the present invention, including a user tray stacker for stackinguser trays which are loaded with semiconductor devices for testing,positioning the user trays at a device supplying position one by one,positioning empty user trays at a device receiving position where theempty user trays receive test-completed semiconductor devices, andstacking user trays which are loaded with the test-completedsemiconductor devices; a device loading portion having double-rowdisplaceable hands for picking up the semiconductor devices from theuser trays at the device supplying position and positioning thesemiconductor devices in a boat which is at a device loading position; aheating/cooling chamber for heating or cooling the semiconductor deviceson the boats according to the test requirements, while de-elevating theboats to a lower outlet, sequentially, by order of boat receipt from thedevice loading portion through an upper inlet, and discharging thesemiconductor devices through a lower outlet; a test chamber forconnecting and testing the heated or cooled semiconductor devices insockets of a test head; a recovering chamber for recovering thetemperature of the semiconductor devices to a normal degree, whileelevating and discharging the boats through the upper end by order ofboat receipt from the test chamber through a lower end of the testchamber; a device sorting portion having a plurality of single-rowdisplaceable hands for picking the test-completed semiconductor devicesfrom the boats by order of boat receipt from the recovering chamber, andstacking the semiconductor devices in a plurality of predetermined areasof a plurality of conveying buffers corresponding to the respectivegrades of semiconductor devices sorted by the testing results; and adevice unloading portion for stacking the semiconductor devices at theconveying buffers in user trays for the respective grades of thesemiconductor devices.

[0017] The device loading portion includes a double-axis loading robotattached to the double-row displaceable hands for positioning thedouble-row displaceable hands above the user trays or the device loadingposition; and a device buffer for temporarily holding sparesemiconductor devices.

[0018] The device unloading portion includes a boat conveying shaft formoving the boats in a forward and backward direction, i.e., X-directionto a device adsorbing position; two single-axis orthogonal robots forpicking up the devices from the boats with a plurality of single-rowdisplaceable hands and positioning the devices to predetermined areas ofconveying buffers corresponding to respective grades of the deviceswhich are evaluated according to the test results; and two conveyingbuffers for carrying the devices from the boats to the device unloadingportion.

[0019] The device unloading portion is a double-axis unloading robotsattached to a pickup hand which is comprised of a plurality of pickupcylinders.

[0020] Further, the above-mentioned objects of the present inventionwill be accomplished by a single and double-row displaceable handsaccording to the present invention.

[0021] The single-row displaceable hand includes a hand frame; a guidingbar disposed on the hand frame; a plurality of pickup blocks insertedby, and slid on the guiding bar; and pickup block pitch adjusting meansfor varying the pitches between the guiding bar and the plurality ofpickup blocks by being elevated or de-elevated with respect to the handframe.

[0022] The pickup block pitch adjusting means includes guidingprotrusions protruding from the plurality of pickup blocks; a pitchadjusting plate having a plurality of guiding grooves formed therein forreceiving the guiding protrusions, in a manner such that the guidingprotrusions at ends of the guiding grooves indicate narrow pitchesbetween the pickup blocks while the guiding protrusions at the oppositeends indicate wider pitches between the pickup blocks; and driving meansfor elevating and de-elevating the pitch adjusting plate. Here, theguiding protrusions are formed of cam followers. Further, the pickupblock pitch adjusting means is mounted on the hand frame and includeselevation guiding means formed on the hand frame for guidingelevation/de-elevation of the pitch adjusting plate. The elevationguiding means includes a linear motion guide (LM guide) disposed on thehand frame; and a linear motion block (LM block) disposed on the pitchadjusting plate.

[0023] The pickup blocks are attached to pickup cylinders forpicking-and-placing the devices.

[0024] Each of the double-row displaceable hands includes a hand frame;a first guiding bar disposed on the hand frame; a plurality of pickupblocks inserted by, and slid on the first guiding bar; first pitchadjusting means for varying the pitches between the first guiding barand the plurality of pickup blocks by being elevated or de-elevated withrespect to the hand frame; width adjusting means mounted on the handframe; a second guiding bar disposed on the width adjusting means; aplurality of pickup blocks inserted by, and slid on the second guidingbar; and second pitch adjusting means for varying the pitches betweenthe second guiding bar and the plurality of pickup blocks by beingelevated or de-elevated with respect to the hand frame.

[0025] The first and second pitch adjusting means include guidingprotrusions protruding from the plurality of pickup blocks; first andsecond pitch adjusting plates having a plurality of guiding groovesformed therein for receiving the guiding protrusions in a manner thatthe guiding protrusions at one ends of the guiding grooves indicatenarrow pitches between the pickup blocks while the guiding protrusionsat opposite ends of the guiding grooves indicate wider pitches betweenthe pickup blocks; and first and second driving means for elevating orde-elevating the first and second pitch adjusting plates.

[0026] The first pitch adjusting means includes first elevation guidingmeans mounted on the hand frame, for guiding the elevation andde-elevation of the first pitch adjusting plate, and, the second pitchadjusting plate comprises second elevation guiding means mounted on thewidth adjusting means, for guiding the elevation or de-elevation of thesecond pitch adjusting plate.

[0027] The width adjusting means includes a pneumatic cylinder mountedon the hand frame; a width adjusting bracket connected to an end of arod of the pneumatic cylinder; a plurality of linear motion blocksmounted on the width adjusting bracket; and a plurality of linear motionguides mounted on the hand frame in a perpendicular relation withrespect to the first guiding bar, for guiding the movement of the linearmotion block.

[0028] The above objects are also accomplished by a rambus handleraccording to the present invention, having the test chamber including aboat loaded with a plurality of semiconductor devices for testing; acontact picker assembly for picking and directly connecting thesemiconductor devices from the boats to the test sockets of the testhead; elevating means for vertically moving the contact picker assembly;and boat conveying means for moving the boats so that the contact pickerassembly can pick and de-elevate the semiconductor devices from theboats to the test sockets.

[0029] The boat is loaded with a plurality of semiconductor devices atthe device loading portion, and moved to the initial test position abovethe test head. The boat has a plurality of device receiving holes and aplurality of piercing holes formed between the device receiving holes.Through the piercing holes of the boat, the contact picker assemblyde-elevates to the test sockets and directly connects the devices to thetest sockets for testing. Meanwhile, the boat is moved from the initialtest position by the boat conveying means across the piercing holes ofthe boat to a distance corresponding to a half pitch of the devicereceiving hole.

[0030] The contact picker assembly includes an elevating plate connectedto the elevating means; a plurality of pickers connected to theelevating plate via a shock absorbing means, and comprised of fourrectangular picking members which have vacuum holes; a vacuum padmovably connected to each picker member to adsorb the devices; and aplurality of compression coil springs disposed between each pickermember and vacuum pad to elastically support the vacuum pad downward.

[0031] The shock absorbing means includes a first shock absorbing plateconnected to upper portion of each picker; a second shock absorbingplate connected to the elevating plate corresponding to the first shockabsorbing plate; a plurality of connecting bars for connecting the firstand second shock absorbing plates in a manner that the first shockabsorbing plate is movable with respect to the second shock absorbingplate within a predetermined range; and a plurality of compression coilsprings disposed around the plurality of connecting bars for elasticallysupporting the first shock absorbing plate to the second shock absorbingplate.

[0032] The contact picker assembly elevating means includes a motormounted on an upper portion of a frame which is mounted on the contactpicker assembly; a rack bar protruding upright from the upper centerportion of the contact picker assembly through the frame, and having arack engaged with the pinion in a lengthwise direction for movingvertically as the motor operates; and guiding means for guiding theelevation/de-elevation of the contact picker assembly.

[0033] The boat conveying means includes a gripping member pivotallydisposed adjacent to the boat, for gripping the boat by beingselectively inserted in a gripping hole formed on one side of the boat;a pivoting portion for pivoting the gripping member until the grippingmember is inserted in the gripping hole; and a driving portion forlinearly moving the gripping member which grips the boat by theoperation of the pivoting portion.

[0034] The pivoting portion includes a pivoting bar for pivotallysupporting the gripping member; a pivoting block connected to an end ofthe pivoting bar; and a pneumatic cylinder for pivoting the pivotingblock. The driving portion includes a motor; a ball screw engaged with ashaft of the motor; a ball nut engaged with the ball screw for linearlymoving along with the rotational movement of the ball screw; and aconnecting member for connecting the ball nut and the pivoting portion.

[0035] According to a preferred embodiment of the present invention, thetest chamber of the rambus handler includes a picking position guidingmeans for guiding the vacuum pads of the contact picker assembly toaccurate positions in the device receiving holes when the contact pickerassembly picks the semiconductor devices; de-elevation guiding means forguiding the contact picker assembly when the contact picker assemblyde-elevates to connect the semiconductor devices to the test sockets;and connecting guiding means for guiding the vacuum pads of the contactpicker assembly to accurate positions in the test sockets when thecontact picker assembly connects the semiconductor device to the testsockets. The picking position guiding means includes first and secondslope guiding portions correspondingly formed on left and right sidesand on both sides of the device receiving holes of the vacuum pads, forguiding an X-directional movement of the vacuum pads in the devicereceiving holes; and first and second hard stop contacting portions of apredetermined radius of curvature, correspondingly formed on front andrear sides, and on both sides of the device receiving holes of thevacuum pads, for guiding an Y-directional movement of the vacuum pads inthe device receiving holes.

[0036] The de-elevation guiding means includes a plurality of pairs ofcontact guiding pins integrally formed on the contact picker assembly;and a contact guide plate disposed on an upper portion of the test head,the guiding plate having a contact guiding pin holes corresponding tothe contact guiding pins.

[0037] The connection guiding means includes third slope guidingportions formed on both side walls of the test sockets corresponding tothe first slope guiding portions of the vacuum pads, for guiding anX-directional movement of the vacuum pads; and third hard stopcontacting portions formed on both sides of the test socketscorresponding to the first hard stop contacting portions of the vacuumpads, for guiding an Y-directional movement of the vacuum pads.

BRIEF DESCRIPTION OF THE DRAWINGS

[0038] A more complete appreciation of the invention, and many of theattendant advantages, thereof, will be readily apparent as the samebecomes better understood by reference to the following detaileddescription when considered in conjunction with the accompanyingdrawings in which like reference symbols indicate the same or similarcomponents, and wherein:

[0039]FIG. 1 is a perspective view for showing a rambus handleraccording to a preferred embodiment of the present invention;

[0040]FIG. 2 is a perspective view for showing a user tray stacker ofFIG. 1;

[0041]FIG. 3 is a perspective view for showing a device sorting sectionof FIG. 1;

[0042]FIG. 4 is a diagram for showing the conveyance path of the devicesin the rambus handler of FIG. 1;

[0043]FIG. 5 is a perspective view for showing a single-row displaceablehand of FIG. 1;

[0044]FIGS. 6A and 6B are views for showing varying pitches between thepickup cylinders of the single-row displaceable hand of FIG. 5, in which

[0045]FIG. 6A shows the pitches being narrowed, while

[0046]FIG. 6B shows the pitches being widened;

[0047]FIG. 7 is a perspective view for showing a double-row displaceablehand;

[0048]FIG. 8 is a perspective view for schematically showing testchambers of the rambus handler according to the preferred embodiment ofthe present invention;

[0049]FIGS. 9A and 9B are front and side views, respectively, forshowing the structure of the test chambers of FIG. 8 in detail;

[0050]FIGS. 10A, 10B, and 10C are views for showing the structure of theboat according to the present invention, in which FIG. 10A is a planview, and FIGS. 10B and 10C are sectional views taken on lines I-I andII-II of FIG. 10A, respectively;

[0051]FIGS. 11A and 11B are plan and sectional views, respectively, forshowing the structure of sockets employed in the test heads of testchambers according to the present invention;

[0052]FIGS. 12A and 12B are plane and sectional views, respectively, forshowing the structure of contact guide plates of the test chambersaccording to the present invention;

[0053]FIGS. 13A, 13B, and 13C are front, bottom, and side elevationviews, respectively, for showing the shape of vacuum pads according tothe present invention;

[0054]FIGS. 14A and 14B are sectional views shown in X and Y directions,respectively, for showing the device being picked by a contact pickerassembly according to the present invention;

[0055]FIGS. 15A and 15B are sectional views shown in X and Y directions,respectively, for showing t he device being connected by the contactpicker assembly according to the present invention;

[0056]FIG. 16 is an enlarged sectional view for showing the main portionof the preferred embodiment of the present invention, i.e., the vacuumpad of the contact picker assembly being connected with the test socket;

[0057]FIGS. 17A and 17B are front views for showing the devices beingadsorbed by a picker, and connected to the test socket, respectively;

[0058]FIG. 18 is a flow chart for explaining a method for testing thedevices in the test chambers of the rambus handler according to thepresent invention; and

[0059]FIG. 19 is a sectional view for showing the main portion of avariation of the present invention in which a TSOP type device beingconnected to the test socket which is developed to test the TSOP typedevices.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0060] Reference will now be made in detail to the preferred embodimentsof the present invention, examples of which are illustrated in theaccompanying drawings.

[0061] As shown in FIG. 1, the rambus handler according to the presentinvention includes a user tray stacker 100, device loading section 200,heating/cooling chamber 300, test chamber 400, recovering chamber 500,device sorting section 600, and device unloading section 700.

[0062] Hereinafter, throughout the description of the preferredembodiment of the present invention, it will be defined that anX-direction is the direction along which tray racks are disposed on theupper front portion of a main frame 1, while an Y-direction is thedirection running toward the rear portion of the main frame 1 in aperpendicular relation with the X-direction. Reference are alsoparticularly made to FIG. 4 for showing the conveyance of the devices 60of the rambus handler.

[0063] The user tray stacker 100 is disposed on the upper front portionof the main frame 1, and as shown in FIG. 2, the user tray stacker 100includes tray racks 110 for stacking the user trays 10, tray fixingplates 120 for fixing the user trays 10 one by one, and a tray robot 130for loading/unloading the user trays 10. Further, on the upper side ofthe user tray stacker 100, a base plate 2 is mounted.

[0064] The tray racks 110 are plates which have guiding bars 111, andstack the user trays 10 one by one. The tray racks 110 areforward-and-backward movable in the Y-direction by cylinders. Aplurality of tray racks 110 are disposed on the upper front portion ofthe main frame in a single row, including two tray racks 110 a forstacking the user trays 10 loaded with the devices 60 for testing, onetray rack 110 b for stacking empty user trays 10, and five tray racks110 c for stacking the user trays 10 loaded with the devices 60 whichare sorted according to the test results.

[0065] The tray fixing plates 120 are disposed above the tray racks 110and below the base plate 2, corresponding to each one of the tray racks110 except the tray rack 110 b loaded with the empty user tray 10. Thetray fixing plates 120 are elevated/de-elevated by the cylinders 121.Accordingly, when the tray fixing plates 120 are elevated with the usertrays 10 loaded thereon, the user trays 10 are fit in and exposedthrough openings formed in the base plate 2, forming device supplyposition P1 and device receiving position P6.

[0066] The tray robot 130 is an orthogonal robot having an X-directionaxis 131 and two vertical-direction axes 133. The vertical-directionaxes 133 have grippers 135, respectively, for loading/unloading the usertrays 10 between the tray fixing plates 120 and the tray racks 110. Theoperational area of the tray robot 130 covers whole tray racks 110.

[0067] The device loading section 200 adsorbs the devices 60 from theuser trays 10 fixed in the device supply position P1 and accommodatesthe devices 60 in the receiving openings of boats 20 located in thedevice loading position P2. The device loading section 200 includesdouble-row displaceable hands 210, loading robots 220, and devicebuffers 230.

[0068] Each double-row displaceable hand 210 includes sixteen pickupcylinders 286 and 296 which are arranged in a manner that the eightpickup cylinders 286 and 296 are arranged in two rows. The pitches ofthe respective cylinders 286 and 296 vary from narrow to wide ranges.The narrow pitches indicate that the devices 60 are picked up from theuser trays 10, while the wide pitches indicate the devices 60 are laidon the boats 20. This will be described in greater detail later.

[0069] The loading robot 220 is a double-axis cartesian coordinate robotwhich has displaceable hands 210 and move in X and Y directions. Theloading robot 220 is disposed at a proper height to cover the operationarea of the user trays 10 in the device supplying position P1 and theboats 20 in the device loading position P2.

[0070] The device buffers 230 are disposed between the device supplyingposition PI and the device loading position P2, having a plurality ofdevice receiving openings formed therein. The device buffers 230 alwayshave two spare devices 60, enabling the double-row displaceable hands210 to adsorb and convey sixteen devices 60 at all times.

[0071] The heating/cooling chamber 300 is located in the upper rearportion of the main frame 1, and has an inlet having the same height asthe device loading position P2 in order for the boat 20 to entertherethrough, and an outlet having the same height as the upper surfaceof the main frame 1 in order for the boat 20 to exit therethrough.Accordingly, the inlet and outlet of the heating/cooling chamber 300 areat different heights. As the boat 20 enters into the heating/coolingchamber 300 and de-elevated toward the outlet, the devices 60 on theboat 20 are properly heated or cooled according to test requirements.

[0072] The test chamber 400 is formed in the main frame 1, andconnectively formed next to the outlet of the heating/cooling chamber300, to connect the devices 60 to the plurality of test sockets of thetest heads located beneath the upper side of the main frame 2 fortesting. The test chamber 400 will be described in greater detail later.

[0073] The recovering chamber 500 is connectively disposed next to thetest chamber 400. The recovering chamber 500 elevates the boat 20, whichcomes out of the test chamber 400, to the height corresponding to thedevice loading position P2, and recovers the temperature of the deviceto a normal temperature. Inlet of the recovering chamber 500 is at thesame height as the outlet of the heating/cooling chamber 300, while theoutlet thereof is formed at the same height as the device loadingposition P2.

[0074] The outlet of the heating/cooling chamber 300, testing positionand conveyance path of the boats 20 at the test chamber 400, and inletof the recovering chamber 500 are all at the same height. The boats 20are conveyed among the respective chambers by a boat conveying devicehaving ball screws and pneumatic cylinders.

[0075] As shown in FIG. 3, the device sorting section 600 includes aboat conveying shaft 610, two single-axis robots 620, two conveyancebuffers 630, and a single-row displaceable hand 640.

[0076] After receiving the boat 20 from the outlet of the recoveringchamber 400, the boat conveying shaft positions the boat 20 properly.The boat conveying shaft 610 includes a motor 611, ball screw 612, andLM guide 613.

[0077] The single-axis robots 620 are disposed on the boat conveyingshaft 610 and the conveying buffers 630, and pick-and-place the devices60 of the boats 20 to the conveying buffers 630. Each single-axis robot620 has eight pickup cylinders 652 which are attached with a single-axisdisplaceable hand 640 for varying the pitches between the cylinders 652.This will be described in greater detail later.

[0078] The conveying buffers 630 are disposed beside the boat conveyingshaft 610. Conveying plates 631 of the conveying buffers 630 areforward-backward moved by a linear conveying means, and have a pluralityof sections for receiving and stacking the devices 60. The linearconveying means includes a motor, ball screw, and LM guide. Accordingly,after the testing of the devices 60, the conveying buffers 630 conveythe devices 60 toward the user tray stackers 100, more specifically tothe device unloading position P5.

[0079] Further, the device sorting section 600 includes a first sectionfor receiving the boat 20 from the recovering chamber 500, and a secondsection for conveying the boat 20, which is 18 emptied as the devices 60thereon are picked and placed to the conveying buffers 630, to thedevice loading position P1 of the device loading section 200. The firstand second devices 60 are generally formed of pneumatic cylinders.

[0080] The device unloading section 700 grades, groups, and stacks thedevices 60 of the conveying buffers 630 according to the test results inthe user trays 10 fixed in the device receiving position P6. The deviceunloading section 700 includes a double-axis unloading robot 710 (aCartesian coordinate robot) attached to the pickup hand 720 for movingin the X and Y directions.

[0081] The unloading robot 710 are disposed at the proper height tocover the device unloading position P5 of the two conveying buffers 630and the user trays 10 in the device receiving position P6 within itsoperation area.

[0082] The pickup hand 720 includes sixteen pickup cylinders 286 and296. Since the pitches between the device receiving sections of theconveying buffers 630 and between the user trays 10 are identical witheach other, the pitches between the pickup cylinders 286 and 296 do notvary. In case when the pitches between the device receiving sectionsvary, the displaceable hand may be used.

[0083] Further, albeit not explained, a controlling section is includedin this embodiment to control the respective sections.

[0084] Hereinafter, the operation of the rambus handler according to thepreferred embodiment of the present invention will be described ingreater detail.

[0085] A worker stacks the user trays 10 loaded with the devices 60 inthe supply tray racks 110 a which are in advanced position. After thestacking, the tray racks 110 a are returned to the initial position.Further, the empty user trays 10 without the devices 60 are stacked inthe empty tray rack 110 b in number at least the same as the number ofdevice grade groups.

[0086] When the user trays 10 are stacked in the tray racks 110, thetray robot 130 detects the Page 18 of 53 position of the upper-most usertray 10 of the user trays 10 in the supply tray racks 110 a, grips theupper-most user tray 10 with the grippers 135 and escapes to above theneighboring tray racks 110 a. Then, the tray fixing plates 120 arede-elevated to the proper height that could enable the grippers 135 ofthe tray robot 130 to load/unload the user trays 10. When the trayfixing plates 120 are de-elevated, the user trays 10 gripped by the trayrobot 130 are loaded on the tray fixing plates 120. When the tray robot130 loads the user trays 10 and escapes, the tray fixing plates 130 areelevated to fit in the user tray 10 and thus expose the user tray 10through the opening formed in the base plate 2, forming the devicesupplying position P1.

[0087] If there is the user tray 10 on the tray fixing plates 120, thetray robot 130 unloads the user tray 10 from the tray fixing plate 120with the gripper unoccupied with the user tray 10, and then proceeds theabove-described operations. After unloading the user tray 10 from thetray fixing plate 120, the tray robot 130 selectively stacks the usertray 10 either in the empty tray rack 110 a or in the other tray racks110 c stacked with the test completed devices 60.

[0088] When the user trays 10 arrive the device supplying position PI,the loading robot 220 adsorbs the device with the double-rowdisplaceable hand 210, and stacks the device in the boat 20 at thedevice loading position P2. Here, the double-row displaceable hand 210adsorbs the devices 60 from the user tray 10 with narrowed pitches amongthe pickup cylinders 283 and 296. While the double-row displaceable hand210 moves to the device loading position P2, the pitches of the pickupcylinders 286 and 286 are widened, and the devices 60 are positioned onthe boat 20 properly.

[0089] If there is a shortage of adsorbed devices 60 from sixteen, it ismade up by a proper process, such as un-adsorbing the devices 60 back tothe device buffers 230, or adsorbing corresponding number of devices 60from the device buffers 230 to make up sixteen devices 60. When there isa shortage of device adsorbed by the displaceable hand 210 with nodevice left on the device buffers 230, the displaceable hand 210un-adsorbs the devices 60 back to the device buffers 230.

[0090] After completely loading the devices 60 on the boat 20 in thedevice loading position P2, the loading robot 220 drags the boat 20 tothe heating/cooling chamber 300 with guiding bars formed on the lowerend of the displaceable hand 210. Next, rotary cylinders formed in frontof the inlet of the heating/cooling chamber 300 completely put the boat20 into the heating/cooling chamber 300.

[0091] As one boat 20 enters into the heating/cooling chamber 300,another boat 20 at the lowest exist out to the test chamber 400. Morespecifically, the inlet and outlet of the heating/cooling chamber 300are at different heights, and a plurality of boats 20 are stackedtherebetween. Accordingly, as one boat 20 enters the heating/coolingchamber 300, another boat 20 exits from the heating/cooling chamber 300sequentially. Since it takes a certain time for the boats 20 in theheating/cooling chamber 300 to exit, the boats 20 are heated or cooledproperly until each exists.

[0092] After exiting from the heating/cooling chamber 300, the boat 20is positioned on the test head of the test chamber 400. Then, the pickerassembly of the test chamber 400 pick and connect the thirty two devices60 to the sockets of the test head for the testing. The controller ofthe handler memorizes the grades of the devices 60 on the boat 20 whichare measured according to the test results. After the testing, the boat20 enters the recovering chamber 500. Testing process in the testchamber 400 will be described in greater detail later.

[0093] Like the heating/cooling chamber 300, the inlet and outlet of therecovering chamber 500 are at different heights. Accordingly, thetemperature of the devices 60 on the boats are returned to a normaldegree in the recovering chamber 500, while the boats 20 aresequentially entered and discharged through the inlet and outlet. Anexception of the test chamber 400 with respect to the heating/coolingchamber 300 is that the outlet is higher than the inlet, and the boatsexit above the test chamber 400.

[0094] After exiting from the recovering chamber 500, the boats 20 arestacked on the boat conveying shaft 610 of the device sorting section600. The boat conveying shaft 610 conveys the boats 20 forward andbackward (i.e., in Y-direction) and stops at the point where thesingle-axis robots 620 adsorb the devices 60 from the boats 20.

[0095] Each single-axis robot 620 adsorbs eight devices 60 from the boat20 with the single-row hand 640, conveys the devices 60 in X-direction,and positions the devices 60 in the device receiving sections of theconveying buffers 630 at a device receiving position P4 according to thegrades of the devices 60 determined by the test results. Since there arearea allotment for the respective grade groups of devices 60 in thehandler controller, the devices 60 adsorbed by the single-axis robots620 can be received in the proper area of the conveying buffers 630according to the test results memorized by the controller. This processis performed by the cooperation of the X-direction movement of thesingle-axis robots 620 and the Y-direction movement of the conveyingbuffers 630. When the devices 60 are drawn by the single-axis robot 620,the emptied boat 20 is moved to the device loading position PI by theboat conveying shaft 610.

[0096] The conveying buffer 630 loaded with the devices 60 are conveyedto the device unloading position P5 by the linear conveying means whichis formed of ball screws. There are two conveying buffers 630 foruninterrupted testing operation. Accordingly, while one conveying buffer630 is moved to the device unloading position P5, the other conveyingbuffer 630 continues receiving and grouping the respective grades ofdevices 60 from the device sorting section 600.

[0097] When the conveying buffers 630 move to the device unloadingposition P5, the unloading robot 710 adsorbs the devices 60 from theconveying buffers 630 with the pickup hand 720 formed of sixteen pickupcylinders, and stacks the respective grade groups of the devices 60 intocorresponding user trays 10 formed at the device receiving position P6.Accordingly, the devices 60 at the first, second, . . . , defectivegrade areas of the conveying buffers 630 are stacked in the user trays10 for first, second, . . . , defective grade devices 60, respectively.

[0098]FIG. 4 is a flow diagram for showing the conveyance path of thedevices 60 in the rambus handler according to the preferred embodimentof the present invention. The devices 60 in the user tray 10 at thedevice supplying position P1 are adsorbed by the double-row displaceablehand 210 by sixteen, and received on the boat 20 t the device loadingposition P2 (shown in arrow A). When the devices 60 are completelyreceived on the boat 20, the boat 20 is conveyed to the heating/coolingchamber 300, test chamber 400, recovering chamber 500, and the devicesorting section 600 (shown in arrow B). When the boat 20 is conveyed tothe device sorting section 600, the respective grades of devices 60 arereceived at the correspondingly allotted areas by the two single-rowdisplaceable hands 640 (shown in arrow C). The emptied boat 20 is thenconveyed to the device loading position P2. When the conveying buffers630 are moved to the device unloading position P5, the respective gradesof the devices 60 are loaded from the conveying buffers 630 to thecorresponding user trays 10 by the fixed hand 720 (shown in arrow D).

[0099] An arrow E shows the movement path of the user trays 10. Asshown, the emptied user tray 10 is moved to be loaded with testcompleted devices 60.

[0100] Hereinafter, the single-row displaceable hand 640 and thedouble-row displaceable hand 210 according to the present invention willbe described in greater detail.

[0101] As shown in FIG. 5, the single-row displaceable hand 640according to the preferred embodiment of the present invention includesa hand frame 641, guiding section 642, a plurality of pickup blocks 644,a plurality of pickup cylinders 652, and pickup cylinder pitch adjustingmeans.

[0102] The guiding section 642 includes two rods which are fixed to bothends of the hand frame 641 at a predetermined distance from each other,while a plurality of pickup blocks 644 are slidably pierced by theguiding rods 642.

[0103] The pickup block pitch adjusting means includes guidingprotrusions protruding from a plurality of pickup blocks 644, a pitchadjusting plate 648, driving means 650, and guiding means 660.

[0104] The pitch adjusting plate 648 includes a plurality of guidinggrooves 648 a for receiving the guiding protrusions 646. The guidingprotrusions at one ends of the plurality of guiding grooves 648 aindicates the contraction of the pickup blocks 644, while the guidingprotrusions at the other ends of the plurality of guiding grooves 648 aindicates extension of the pickup blocks 644.

[0105] The driving means 650 elevates the pitch adjusting plate 648, andincludes two pneumatic cylinders. At both upper ends of the pitchadjusting plate 648, rods of the pneumatic cylinders are fixed, whilethe bodies thereof are fixed to the hand frame 641.

[0106] The guiding means 660 guides the elevation/de-elevation of thepitch adjusting plate 648 when the pitch adjusting plate 648 is elevatedor de-elevated by the driving means 650. The guiding means 660 includeslinear motion guides 664 and motion blocks 662. The linear motion guides664 are formed on both ends of the hand frame 641, while the linearmotion blocks 662 are formed on both ends of the pitch adjusting plate648 for guiding linear elevation/de-elevation.

[0107] Further, on both sides of each pickup block 644, pickup cylinders652 are mounted for adsorbing and conveying a certain number of devices60 (not shown).

[0108] The operation of the single-row displaceable hand 640 will bedescribed in greater detail below.

[0109] When conveying the densely arrange devices 60 to the less densestate, such as conveying the devices 60 from the user tray 10 to theboat 20, the single-row displaceable hand 640 is used as follows:

[0110] As shown in FIG. 6A, the single-row displaceable hand 640 isinitially in tight contact with the pickup blocks 644. As the rods ofthe pneumatic cylinders of the driving means 650 are elevated, the pitchadjusting plate 648 attached to the rods are moved upward along thelinear motion guides 664. Accordingly, a plurality of guiding grooves648 a formed in the pitch adjusting plate 648 are also elevated, and theguiding protrusions 646 received in the guiding grooves 648 a are movedin the guiding grooves 648 a, widening the pitches between the guidingprotrusions 646.

[0111] The guiding protrusions 646 include cam followers, which areattached to a plurality of pickup blocks 644. Since the pickup blocks644 are slidably pierced by the guiding rods 642, the pickup blocks 644slid along the guiding rods 642 by the elevating movement of the pitchadjusting plate 648, widening the pitches between the pickup blocks 644as much as the horizontal distance of the movement of the guidingprotrusions 646.

[0112] That is, as shown in FIG. 6B, the single-row displaceable hand640 un-adsorbs the devices 60 in a state that the pitches between thedevices 60 are widened.

[0113]FIG. 7 is a perspective view for showing the double-rowdisplaceable hand according to another preferred embodiment of thepresent invention.

[0114] In the second preferred embodiment, as shown in FIG. 7, aplurality of pickup cylinders are arranged in two rows, capable ofvarying the pitches therebetween.

[0115] The double-row displaceable hand 210 mainly includes a hand frame241, first and second guiding rods 242 and 244, a plurality of pickupblocks 282, first and second pitch adjusting means, and width adjustingmeans 270.

[0116] The first guiding rod 242 includes two guiding rods 242 which arefixed to both ends of the hand frame 241 at a predetermined distancetherebetween, while a plurality of pickup blocks 282 are slidablypierced by the two first guiding rods 242.

[0117] The first pitch adjusting means includes guiding protrusions 284protruding from a plurality of pickup blocks 282, first pitch adjustingplate 280, first driving section 246, and first elevation guidingsection 250.

[0118] The first pitch adjusting plate 280 has a plurality of guidinggrooves 280 a for receiving the guiding protrusions 284, respectively.The plurality of guiding grooves 280 a at one ends of the guidinggrooves 280 a indicates a narrow pitches between the pickup blocks 282,while the guiding protrusions 280 a at the other ends of the guidinggrooves 280 a indicates a wide pitches between the pickup blocks 282.

[0119] The first driving section 246 elevates the first pitch adjustingplate 280, and includes two pneumatic cylinders. Rods of the pneumaticcylinders are fixed at both upper sides of the first pitch adjustingplate 280, while the bodies thereof are fixed on the hand frame 241.

[0120] The first elevation guiding section guides theelevation/de-elevation of the first pitch adjusting plate 280 when thefirst pitch adjusting plate 280 is elevated by the first driving section246. The first elevation guiding section 250 includes linear motionguides 254 and linear motion blocks 252. The linear motion guides 254are disposed on both ends of the hand frame 241, while the linear motionblocks 252 are disposed on both ends of the first pitch adjusting plate280 for guiding linear movement of the first pitch adjusting plate 280.

[0121] The width adjusting section 270 includes two pneumatic cylinders272, four linear motion guides 276 and linear motion blocks 274, andsub-frame 278. The linear motion guides 276 are formed on the hand frame241 in a perpendicular relation with respect to the first guiding rods242. Here, the linear motion guides 276 are disposed on both sides ofthe hand frame 241, one above and the other below the first guiding rods242. The linear motion guides 276 are connected with the linear motionblocks 274, respectively, while the linear motion blocks 274 areconnected with the sub-frame 278. To both upper sides of the sub-frame278, rods of two pneumatic cylinders 272 are connected, respectively,while the pneumatic cylinders 272 are fixed on the hand frame 241.

[0122] The second guiding rod 244 includes two guiding rods 244 arefixed on the sub-frame 278 at a predetermined distance from each other.That is, both ends of each second guiding rod 244 are fixed on thesub-frame 278. The pickup blocks 292 are slidably pierced by the twosecond guiding rods 244.

[0123] The second pitch adjusting means includes guiding protrusionsprotruding from the pickup blocks 292, respectively, second pitchadjusting plate 290, second driving section 248, and second elevationguiding section 260.

[0124] The second pitch adjusting plate 290 includes a plurality ofguiding grooves for receiving the guiding protrusions. The guidingprotrusions at one ends of the guiding grooves indicates narrow pitchesbetween the pickup blocks 292, while the guiding protrusions at theother ends of the guiding grooves indicates wide pitches between thepickup blocks 292.

[0125] The second driving section 248 elevates the second pitchadjusting plate 290, and includes two pneumatic cylinders. Rods of thepneumatic cylinders are fixed on both upper sides of the second pitchadjusting plate 290, while the bodies thereof are fixed on the sub-frame278.

[0126] The second elevation guiding section 260 guides the elevation ofthe second driving section 248, when the second pitch adjusting plate290 is elevated by the second driving section 248. The second elevationguiding section 260 includes linear motion guides and linear motionblocks. Here, the linear motion guides are disposed on both ends of thesub-frame 278, while the linear motion blocks are disposed on both endsof the second pitch adjusting plate 290 for guiding the linear movementof the second pitch adjusting plate 290.

[0127] Further, on the respective sides of the pickup blocks, pickupcylinders 286 and 286 are mounted for adsorbing and conveying a certainnumber of devices 60.

[0128] Hereinafter, the operation of the double-row displaceable handaccording to the preferred embodiment of the present invention will bedescribed in greater detail.

[0129] Here, since varying the pitches between the pickup cylinders isdescribed above when describing the operation of the single-rowdisplaceable hand 640, the description will now be focused on theoperation for varying the pitches between the first pickup cylinders 288and between the second pickup cylinders 298.

[0130] When the rods of the pneumatic cylinders 272, which are fixed onthe hand frame 241, are advanced, the sub-frame 278 connected to therods of the pneumatic cylinders 272 are linearly moved along the linearmotion guides 276, to thereby widen the pitches between the first pickupcylinders 288 and between the second pickup cylinders 298. When the rodsof the pneumatic cylinders 272 are retreated, the pitches between thefirst pickup cylinders 288 and between the second pickup cylinders 298are narrowed.

[0131] Although there is no limit for the number of pickup cylinders 288and 298, it is preferable that eight cylinders be arranged in each oftwo rows, i.e., sixteen cylinders are preferred to be used as in thisembodiment.

[0132] Finally, the testing means provided to the test chamber of therambus handler and its operation and effect according to the presentinvention will be described in greater detail.

[0133]FIG. 8 is a schematic perspective view for showing the testchamber of the rambus handler according to the preferred embodiment ofthe present invention. FIGS. 9A and 9B are front and side elevationviews for showing the structure of the test chamber of FIG. 8 in greaterdetail.

[0134]FIGS. 11A and 11B are plan and sectional views, respectively, forshowing the structure of sockets employed in the test heads of testchambers according to the present invention. FIGS. 12A and 12B are planeand sectional views, respectively, for showing the structure of contactguide plates of the test chambers according to the present invention.

[0135]FIGS. 13A, 13B, and 13C are front, bottom, and side elevationviews, respectively, for showing the configuration of vacuum padsaccording to the present invention. FIGS. 14A and 14B are sectionalviews shown in X and Y directions, respectively, for showing the devicebeing picked by a contact picker assembly according to the presentinvention. FIGS. 15A and 15B are sectional views shown in X and Ydirections, respectively, for showing the device being connected by thecontact picker assembly according to the present invention. FOG. 16 isan enlarged sectional view for showing the main portion of the preferredembodiment of the present invention, i.e., the vacuum pad of the contactpicker assembly being connected with the test socket.

[0136] The test head 490 is connected to a tester (not shown), and isformed on the lower portion of the test chamber 400 of the rambushandler. As shown in FIG. 9B, the test head 490 is provided with aplurality of test sockets 491 arranged thereon. For testing, the devices60 are inserted, and thus electrically connected in the test sockets491. A plurality of connecting pins 492 are formed in the test sockets491 in an area array arrangement over the whole lower area of the testsockets 491 for testing the BGA or CSP type devices 60. Further, eachtest socket 491 has third slope guiding sections 411 a formed on bothleft and right sides for guidance when the devices 60 are connected tothe test sockets 491 by the contact picker assembly 430, and third hardstop contacting sections 411 b formed on both front and rear sides toserve the same purpose as the third slope guiding sections 411 a, whichwill be described later in greater detail.

[0137] The boats 20 carry the devices 60 to the initial testing positionon the upper portion of the test head 490. As shown in FIGS. 10A, 10B,and 10C, each boat 20 includes a square body 21, a plurality ofreceiving hoes 22 formed on the body 21 to receive the devices 60, andpiercing holes 23 of a predetermined size formed between the receivingholes 22. Although this embodiment depicts the device arrangement inwhich thirty two (32) devices 60 are arranged in the device receivingholes 22 by four columns and eight rows and the boats respectively haveeighteen (18) piercing holes 23 formed between the receiving holes 22,the number of device receiving holes 22 and the piercing holes 23 may beincreased. Further, second slope guiding sections 22 a are formed in theleft and right sides of each device receiving hole 22 of the boat 20 toguide the devices 60 when the devices 60 are picked up by the contactpicker assembly 430. Second hard stop contacting sections 22 b are alsoformed on front and rear sides of the receiving holes 22 to serve thesame purpose as the second slope guiding sections 22 a, which will bedescribed later in greater detail.

[0138] The contact picker assembly 430 is vertically movable on theupper portion of the test head 490. Accordingly, after picking a certainnumber of devices 60 from the device receiving holes 22 of the boat 20at the initial testing position to a predetermined height, the contactpicker assembly 430 de-elevates the devices 60 into the test sockets 491to thereby electrically connecting the devices 60 to the test sockets491 for testing. As shown in FIGS. 8, 9A and 9B, such a contact pickerassembly 430 includes a plurality of pickers 431, an elevation plate434, and shock absorbing means 438.

[0139] The pickers 431 include four picker members 432 substantially inthe shape of square preferably rectangle. The picker members 432 includevacuum spaces 437 vertically defined therewithin, respectively. Theupper portions of the picker members 432 are connected with vacuum hoses437, while the lower portions thereof are connected to vacuum pads 433for adsorbing the devices 60. The vacuum pads 433 are connected to thepicker members 432 in a manner such that the vacuum pads 433independently move within a predetermined range with respect to thepicker members 432. Between the picker members 432 and the vacuum pads433. Compression coil springs 435 are disposed to elastically supportthe vacuum pads 433 toward the picker members 432 downwardly.Accordingly, when there is assembly error by the contact picker assembly431 and position of the certain vacuum pad 433 deviates from originallyintended position for socket connection, the certain vacuum pad 433moves to adjust its position to thereby, the devices 60 can be insertedin the intended sockets, accurately. Although it is preferable that eachpicker 431 has four vacuum pads 433, it is not strictly limited thereto.Accordingly, numbers and arrangement of the vacuum pads 433 and thepickers 431 may vary depending on certain situations.

[0140] As shown in FIGS. 13A, 13B, and 13C, each vacuum pad 433 includesfirst slope guiding sections 433 a formed on left and right sides,corresponding to the second slope guiding sections 22 a of the devicereceiving holes 22 and the third slope guiding sections 491 a of thesockets 491. Each vacuum pad 433 also includes first hard stopcontacting sections 433 b formed on front and rear sides thereof,corresponding to the second hard stop contacting sections of the devicereceiving holes 22 and the third hard stop contacting sections 491 b ofthe sockets 491.

[0141] Here, as shown in FIG. 14A, the first slope guiding sections 433a of the vacuum pads 433 and the second slope guiding sections 22 a ofthe device receiving holes 22 guide the X-directional movement of thevacuum pads 433 within the device receiving holes 22. Also, as shown inFIG. 14B, the first hard stop contacting sections 433 b of the vacuumpads 433 and the second hard stop contacting sections 22 b of the devicereceiving holes 22 guide the Y-directional movement of the vacuum pads433 within the device receiving holes 22. As a result, the vacuum pads433 are enabled to adsorb the devices 60 at an accurate pickingposition, and accordingly, picking error can be minimized.

[0142] Further, as shown in FIG. 15A, the first slope guiding sections433 a and the third slope guiding sections 491 a of the sockets 491guide the X-directional movement of the vacuum pads 433 within thesockets 491, while as shown in FIG. 15B, the first hard stop contactingsections 433 b of the vacuum pads 433 and the third hard stop contactingsections 49 lb of the sockets 491 guide the Y-directional movement ofthe vacuum pads 433 within the sockets 491. Accordingly, since thevacuum pads 433 can insert and electrically connect the devices 60 intothe sockets 491 accurately, any possibility of having defectiveconnection can be prevented.

[0143] Meanwhile, between the pickers 431 and elevation plate 434, shockabsorbing means 438 are disposed to absorb excessive weight to thepickers 431. Also on the lower sides of the pickers 431, pairs ofcontact guide pins 436 are formed to guide the de-elevation of thepickers 431.

[0144] The elevation plate 434 supports the pickers 431, enabling theplurality of pickers 431 to simultaneously pick and connect the devices60 to the test sockets 491.

[0145] The shock absorbing means 438 are disposed between the pickers431 and the elevation plate 434, to elastically connect the pickers 431to the elevation plate 434 in a manner that the pickers 431 are movablewithin a predetermined range with respect to the elevation plate 434.The shock absorbing means 438 include first shock absorbing plates 438 bconnected to the upper portions of the pickers 431, second shockabsorbing plates 438 b connected to the elevation plate 434corresponding to the first shock absorbing plates 438 a, linking bars438 c for connecting the first shock absorbing plates 438 a to thesecond shock absorbing plates 438 b in a manner that the first shockabsorbing plates 438 a are movable with respect to the second shockabsorbing plates 438 b within a predetermined range, and compressioncoil springs 438 d disposed around the linking bars 438 c forelastically supporting the first shock absorbing plates 438 a to thesecond shock absorbing plates 438 b. Accordingly, the pickers 431elastically move in contact with the test sockets 491, to accuratelyconnect the devices 60 to the test sockets 491.

[0146] Contact picker assembly elevating means 440 is also provided. Thecontact picker assembly elevating means 440 vertically moves the contactpicker assembly 430, picking the devices 60 from the boat 20 with itspickers 431, to thereby insert and electrically connect the devices 60into the test sockets 491. As shown in FIGS. 8, 9A and 9B, the elevationmeans 440 includes a driving source, i.e., a motor 441, pinion 442, rackbar 443, and guiding section 444.

[0147] The motor 441 is fixedly mounted on an upper portion of the frame445 which is mounted on the contact picker assembly 430. The motor 441is an AC servo-motor.

[0148] The pinion 442 is engaged with the shaft of the motor 441. Therack bar 443 is passed through the upper portion of the contact pickerassembly 430, more specifically, the rack bar 443 stands upright fromthe center upper portion of the elevation plate 434, and passed throughthe frame 445. The rack bar 443 includes a rack 443 a toothed with thepinion 442 in a lengthwise direction. Accordingly, the rack bar 443 isvertically moved when the motor 441 operates.

[0149] The guiding section 444 guides the elevation of the contactpicker assembly 430. The guiding section 444 includes a pair of guidingshafts 444 a fixedly protrude from both upper sides of the elevationplate 434 through the frame 445, and a pair of guiding bushes 444 bfixed on the frame 445 to movably support the guiding shafts 444 a.

[0150] Boat conveying means 450 is also provided. The boat conveyingmeans 450 moves boats 20 from the initial test position by a distancecorresponding to a half of the pitch of a device receiving hole 22, tothereby enabling the contact picker assembly 430 picking the devices 60to de-elevate the devices 60 to the test sockets 491 through thepiercing holes 23 of the boats 20. Accordingly, the contact pickerassembly 430 is enabled to pick the devices 60 from the boats 20 at theinitial test position, and de-elevate and insert the devices 60 into thetest sockets 491 through the piercing holes 23 of the boats 20 moved ata distance of a half pitch. The boar conveying means 450 includes agripping member 451, pivoting section 452 and driving section 453.

[0151] The gripping member 451 is inserted in a gripping hole 25 formedon a side of the boat 20, to pivot adjacent to the boat 20 and thusselectively grip the boat 20. Here, the gripping hole 25 may include twoholes formed in front and rear ends of the boat 20. Also, an end of thegripping member 451 may be shaped to correspond to the gripping hole 25.

[0152] The pivoting section 452 supports the gripping member 451, andpivots the gripping member 451 into the gripping hole 25. The pivotingsection 452 includes a pivoting bar 452 a for pivotally supporting thegripping member 451, a pivoting block 452 b connected to the end of thepivoting bar 452 a, and a pneumatic cylinder 452 c connected to theopposite end from the pivoting bar-connected end for pivoting thepivoting block 452 b. When the pneumatic cylinder 452 c operates, thepivoting block 452 b pivots, and accordingly, the pivoting bar 452 aconnected to the pivoting block 452 b pivots. As a result, the grippingmember 451 is inserted in the gripping hole 25 of the boat 20.

[0153] The driving section 453 linearly moves the gripping member 451which grips the boat 20 in cooperation with the pivoting section 452.The driving section 453 includes a driving source, i.e., a motor 453 a,a ball screw 453 b connected to the shaft of the motor 453 a, a ball nut453 c for linearly moving according to the rotational movement of theball screw 453 b, and a connecting member 453 d for connecting the ballnut 453 c with the pivoting bar 452 a of the pivoting section 452. Thepivoting bar 452 a is passed through the connecting member 453 d andpivotally connected to the pivoting block 452 b. The pivoting block 452b is supported on the other side of the connecting member 453 d.Accordingly, when the motor 453 a operates, the ball nut 453 c islinearly moved along the ball screw 453 b connected to the motor 453 a,and the pivoting bar 452 a connected to the ball nut 453 c through theconnecting member 453 d is moved in the advancing direction of the ballnut 453 c, moving the boat 20.

[0154] Meanwhile, as shown in FIG. 9B, the contact guide plate 460 ismounted on the test head 490, to guide the connection of the devices 60into the sockets 491 by the pickers 431. As shown in FIGS. 12A and 12B,the contact guide plate 460 includes a plurality of socket exposingholes 462 formed in a square body 461 in the same arrangement as of thetest sockets 491 in the test head 490. The pickers 431 insert andconnect the devices 60 in the test sockets 491 through the socketexposing holes 462. Further, the contact guide plate 460 includes aplurality of contact guiding pin holes 463 formed between the respectivesocket exposing holes 462. The contact guiding pin holes 463 receive thecontact guiding pins 436 protruding from the pickers 431 during thede-elevation of the pickers 431, to thereby guide the connection of thedevices 60 into the test sockets 491. As a result, the devices 60 can beaccurately inserted in the sockets 491 and electrically connected to thecontacting sections 492 of the sockets 491.

[0155] Hereinafter, position adjustment when the contact picker assembly430 adsorbs the devices 60 for testing will be described in greaterdetail.

[0156] When the rambus handler operates, and the boat 20 loaded with aplurality of devices 60 to be tested thereon is moved to the testposition of the test head 490, the contact picker assembly 430 isde-elevated to the boat 20 by the contact picker assembly elevatingmeans 440, adsorbs a predetermined number of devices 60 from the boat20, and elevates.

[0157] Next, the boat 20 is moved by a half of pitch of the receivinghole 22 by the boat conveying means 450, aligning the piercing holes 23of the boat 20 with the sockets 491 of the test head 490.

[0158] Then the contact picker assembly 430 is de-elevated by thecontact picker assembly elevating means 440, through the piercing holes23 and to the sockets 491, to insert and connect the devices 60 in thesockets 491. As shown in FIG. 8, during the de-elevation of the pickers431, movement of the pickers 431 are first guided while a pair ofcontact guiding pins 436 formed on both sides of the pickers 431 areinserted in the contact guiding pin holes 461 of the contact guidingplate 460 mounted on the test head 490. Here, even when the contactguiding pins 436 are inserted in the contact guiding pin holes 461 ofthe contact guiding plate 460, certain number of vacuum pads 433 may notbe accurately connected in the sockets 491 due to assembly errors of thecontact picker assembly 430, causing defective connections. According tothe present invention, however, corresponding vacuum pads 433compensates the position errors, and the devices 60 can be accuratelyconnected.

[0159] For example, as shown in two-dotted line of FIG. 16, when acertain vacuum pad 433 is inaccurately inserted in the socket 491, thevacuum pad 433, which is movably connected to the picker member 32 a,moves and adjusts its position to an originally intended position in thesockets 491 as shown in a solid line of FIG. 16. As a result, a possibledefective connection can be prevented.

[0160] After an elapse of a predetermined time from connecting thedevices 60 in the sockets 491, the contact picker assembly 430 iselevated to the initial test position through the piercing holes 23 ofthe oat 20. After that, the contact picker assembly 430 de-elevates toload the test completed devices 60 on the boat 20 which is returned tothe initial test position.

[0161] Hereinafter, the testing operation in the test chamber of therambus handler constructed according to the present invention will bedescribed in greater detail with reference to FIGS. 17A, 17B, and 18.

[0162]FIGS. 17A and 17B are front views for showing the devices 60 beingadsorbed by a picker, and connected to the test socket, respectively.FIG. 18 is a flow chart for explaining a method for testing the devices60 in the test chambers of the rambus handler according to the presentinvention.

[0163] First, a plurality of devices 60 are lifted from the deviceloading section 200 and stacked in the device receiving holes 22 of theboat 20 (step S100). The boat 20 stacked with the devices 60 are movedto the test chamber 400 of the rambus handler through a predeterminedset of paths and stops at the initial test position on the test head 490of the test chamber 400 (step S110).

[0164] When the boat 20 is stopped at the upper portion of the test head90, the pickers 431 thereabove de-elevate to adsorb and pick a certainnumber of devices 60 (step S120). After picking the devices 60, thepickers 431 elevate to the initial test position.

[0165] When the pickers 431 elevate, the boat conveying means 450 movesthe boat 20 from the initial test position by a distance correspondingto a half of the pitch of the piercing hole 23 of the boat 20, to alignthe respective piercing holes 23 of the boat 20 with the elevation path(step S130).

[0166] After that, the pickers 431 de-elevate to the test sockets 491through the piercing holes 23 of the boat 20 and insert and electricallyconnect the devices 60 in the test sockets 491 (step S140). Here, sincethe pickers 431 elastically contact with the sockets 491 due to theshock absorbing means 438, the devices 60 can be connected with theconnection pins 492 of the sockets 491 at a uniform pressure. Then thetest process is carried out (step S 150).

[0167] When the test is completed, the pickers 431, picking the devices60, elevate to the initial test position through the piercing holes 23of the boat 20. After the pickers 431 elevate to the initial testposition, the boat 20 is returned to the initial test position (step S160).

[0168] When the boat 20 is returned to the initial test position, thepickers 431 de-elevate to stack the devices 60 in the receiving holes 22of the boat (step S170), and elevate to the initial test position (stepS180).

[0169] Until all the intended devices 60 undergo the testing process,the processes described above repeat.

[0170] As described above, in the rambus handler according to thepresent invention, the boat having a plurality of receiving holes 22 andpiercing holes 23 formed between the receiving holes 22, is used. First,the pickers 431 adsorb a certain number of devices 60 from the boat 20,convey the boat 20 by a distance corresponding to a half pitch of thepiercing hole 23 to align the piercing holes 23 of the boat 20 with thesockets 491 of the test head 490. Then, by de-elevating the pickers 431to the sockets 491 through the piercing holes 23 of the boat 20, thedevices 60 picked by the pickers 431 are connected to the sockets 491,directly.

[0171] Although the preferred embodiments described a means and methodfor testing devices 60 in Area Array Arrangement such as BGA or CSP typedevices 60, the present invention may be also applied to TSOP typedevices which have a plurality of electrodes protruding from both sidesof package.

[0172]FIG. 19 shows the main portion of the test chamber of the rambushandler partially modified to test the TSOP type devices.

[0173] As shown in FIG. 19, connecting pins 492′ are arranged at bothsides of the sockets 491′ in the same arrangement as the electrodes ofdevices 70. Vacuum pads 433′ connected to ends of the pickers havenonconductive pressing members 433′a for pressing the electrodes of thedevices 70 when the devices 70 are connected to the sockets by thevacuum pads 433′.

[0174] Since the construction and operations of the other elements arealready described earlier, repetitious description thereof will beomitted.

[0175] Accordingly, not only the BGA or CSP type devices 60, but alsothe TSOP type devices 70 can be automatically tested by being connectedto the test sockets directly through a partial modification.

[0176] As described above, according to the present invention, therambus handler is capable of testing rambus type devices such as BGA orCSP type devices, automatically.

[0177] Further, according to the present invention, even when thepitches of the receiving holes are varied during the picking-and-placingoperation on the devices, since the cam followers as the guidingprotrusions are guided through the guiding grooves of the pitchadjusting plate and adjust the pitches between the respective cylinders,cumulative errors can be prevented. Further, since the present inventionpicks-and-places sixteen (16) devices at a time, picking-and-placingoperation time can be reduced, while the work efficiency of the testingequipment improves.

[0178] Further, according to the present invention, even when theposition of the vacuum pads varies from its originally intended place inthe socket due to assembly error of the contact picker assembly, etc.,the vacuum pad moves in contact with the socket to the originallyintended place of the socket. Accordingly, any possibility of havingdefective connection between the device and socket can be prevented,while the reliability of the test improves.

[0179] Although the preferred embodiment of the present invention hasbeen shown and described, it will be appreciated by those skilled in theart that changes may be made in these embodiments without departing fromthe principles and spirit of the invention, the scope of which isdefined in the claims and their equivalents.

What is claimed is:
 1. A rambus handler comprising: a user tray stackerfor stacking user trays which are loaded with semiconductor devices fortesting, positioning the user trays at a device supplying position oneby one, positioning empty user trays at a device receiving positionwhere the empty user trays receive test-completed semiconductor devices,and stacking user trays which are loaded with the test-completedsemiconductor devices; a device loading portion having double-rowdisplaceable hands for picking up the semiconductor devices from theuser trays at the device supplying position and positioning thesemiconductor devices in a boat which is at a device loading position; aheating/cooling chamber for heating or cooling the semiconductor devicesaccording to the test requirements, while de-elevating and dischargingthe boats through a lower opening, sequentially, by order of boatreceipt from the device loading portion through an upper opening; a testchamber for connecting and testing the heated or cooled semiconductordevices in sockets of a test head; a recovering chamber for recoveringthe temperature of the semiconductor devices to a normal degree, whileelevating and discharging the boats through an upper end, sequentially,by order of boat receipt from the test chamber through a lower end; adevice sorting portion having a plurality of single-row displaceablehands for picking the test-completed semiconductor devices from theboats by order of boat discharge from the recovering chamber, andstacking the semiconductor devices in a plurality of predetermined areasof a plurality of conveying buffers corresponding to the respectivegrades of semiconductor devices sorted by the testing results; and adevice unloading portion for stacking the semiconductor devices at theconveying buffers in the user trays which are for the respective gradesof the semiconductor devices.
 2. The rambus handler as claimed in claim1 , wherein the device loading portion comprises a double-axis loadingrobot attached to the double-row displaceable hands, positioning thedouble-row displaceable hands above the user trays or the device loadingposition; and a device buffer for temporarily holding sparesemiconductor devices.
 3. The rambus handler as claimed in claim 1 ,wherein each of the single-row displaceable hands comprises: a handframe; a guiding bar disposed on the hand frame; a plurality of pickupblocks inserted by, and slid on the guiding bar; and pickup block pitchadjusting means for varying the pitches between the guiding bar and theplurality of pickup blocks by being elevated or de-elevated with respectto the hand frame.
 4. The rambus handler as claimed in claim 3 , whereinthe pickup block pitch adjusting means comprises: guiding protrusionsprotruding from the plurality of pickup blocks; a pitch adjusting platehaving a plurality of guiding grooves formed therein for receiving theguiding protrusions, in a manner such that the guiding protrusions atends of the guiding grooves indicate narrow pitches between the pickupblocks while the guiding protrusions at the opposite ends indicate widerpitches between the pickup blocks; driving means for elevating andde-elevating the pitch adjusting plate; and elevation guiding meansformed on the hand frame for guiding elevation/de-elevation of the pitchadjusting plate.
 5. The rambus handler as claimed in claim 4 , whereinthe elevation guiding means comprises: a linear motion guide (LM guide)disposed on the hand frame; and a linear motion block (LM block)disposed on the pitch adjusting plate.
 6. The rambus handler as claimedin claim 3 , wherein the pickup blocks comprise pickup cylindersattached thereto for picking-and-placing the semiconductor devices. 7.The rambus handler as claimed in claim 1 , wherein each of thedouble-row displaceable hands comprises: a hand frame; a first guidingbar disposed on the hand frame; a plurality of pickup blocks insertedby, and slid on the first guiding bar; first pitch adjusting means forvarying the pitches between the first guiding bar and the plurality ofpickup blocks by being elevated or de-elevated with respect to the handframe; width adjusting means mounted on the hand frame; a second guidingbar disposed on the width adjusting means; a plurality of pickup blocksinserted by, and slid on the second guiding bar; and second pitchadjusting means for varying the pitches between the second guiding barand the plurality of pickup blocks by being elevated or de-elevated withrespect to the hand frame.
 8. The rambus handler as claimed in claim 7 ,wherein the first and second pitch adjusting means comprise: guidingprotrusions protruding from the plurality of pickup blocks; first andsecond pitch adjusting plates having a plurality of guiding groovesformed therein for receiving the guiding protrusions in a manner suchthat the guiding protrusions at one ends of the guiding grooves indicatenarrow pitches between the pickup blocks while the guiding protrusionsat the opposite ends of the guiding grooves indicate wider pitchesbetween the pickup blocks; and first and second driving means forelevating or de-elevating the first and second pitch adjusting plates.9. The rambus handler as claimed in claim 7 , wherein the first pitchadjusting means comprises a first elevation guiding means mounted on thehand frame, for guiding the elevation and de-elevation of the firstpitch adjusting plate, and, the second pitch adjusting means comprisessecond elevation guiding means mounted on the width adjusting means, forguiding the elevation or de-elevation of the second pitch adjustingplate.
 10. The rambus handler as claimed in claim 7 , wherein the widthadjusting means comprises: a pneumatic cylinder mounted on the handframe; a width adjusting bracket connected to an end of a rod of thepneumatic cylinder; a plurality of linear motion blocks mounted on thewidth adjusting bracket; and a plurality of linear motion guides mountedon the hand frame in a perpendicular relation to the first guiding bar,for guiding the linear motion blocks.
 11. The rambus handler as claimedin claim 1 , wherein the test chamber comprises: a test head having aplurality of test sockets in which the semiconductor devices areinserted for testing; a boat having a plurality of receiving holes forreceiving the semiconductor devices and a plurality of piercing holesformed between the receiving holes, the boat for carrying a plurality ofsemiconductor devices to an initial test position above the test head; acontact picker assembly disposed above the test head to be moved in avertical direction, the contact picker assembly having buffering means,the contact picker assembly for picking the semiconductor devices fromthe boats and connecting the semiconductor devices directly to the testsockets of the test head; elevating means for vertically moving thecontact picker assembly; and boat conveying means for moving the boatsfrom the initial test position by a distance of a half pitch of thedevice receiving hole, to where the contact picker assembly picking thesemiconductor devices can de-elevate to the test sockets through thepiercing holes of the boats.
 12. The rambus handler as claimed in claim11 , wherein the contact picker assembly comprises: a plurality ofpickers having four rectangular picker members having vacuum pads formedon ends thereof for adsorbing the semiconductor devices; an elevationplate for supporting the plurality of pickers in a manner such that theplurality of pickers simultaneously adsorb and directly connect apredetermined number of semiconductor devices in the test sockets; andshock absorbing means formed between the elevation plate and thepickers, for absorbing and relieving the shock when the semiconductordevices are connected in the test sockets by the pickers.
 13. The rambushandler as claimed in claim 11 , wherein the shock absorbing meanscomprises: first absorbing plates connected to upper portions of thepickers; second absorbing plates connected to the elevation plate,corresponding to the first absorbing plates; a plurality of connectingbars for connecting the first and second absorbing plates in a mannerthat the first absorbing plates are moved with respect to the firstabsorbing plates within a predetermined movement range; and a pluralityof compression coil springs disposed around the plurality of connectingbars for elastically supporting the first absorbing plates with respectto the second absorbing plates.
 14. The rambus handler as claimed inclaim 11 , wherein the contact picker assembly elevating meanscomprises: a motor disposed on one upper side of a frame which ismounted on the contact picker assembly; a pinion engaged with a shaft ofthe motor; a rack bar protruding upright from an upper center portion ofthe contact picker assembly and piercing through the frame, the rack barhaving a rack engaged with the pinion in a lengthwise direction formoving vertically as the motor operates; and guiding means for guidingthe elevation or de-elevation of the contact picker assembly.
 15. Therambus handler as claimed in claim 14 , wherein the guiding meanscomprises: a pair of guiding shafts protruding upright from both uppersides of the contact picker assembly and piercing through the frame; anda pair of guiding bushes formed on the frame for movably supporting theguiding shafts.
 16. The rambus handler as claimed in claim 11 , whereinthe boat conveying means comprises: a gripping member pivotally disposedadjacent to the boat, for gripping the boat by being selectivelyinserted in a gripping hole formed on one side of the boat; a pivotingportion for pivoting the gripping member until the gripping member isinserted into the gripping hole; and a driving portion for linearlymoving the gripping member which grips the boat with the assistance ofthe pivoting portion.
 17. The rambus handler as claimed in claim 16 ,wherein the pivoting portion comprises: a pivoting bar for pivotallysupporting the gripping member; a pivoting block connected to an end ofthe pivoting bar; and a pneumatic cylinder for pivoting the pivotingblock.
 18. The rambus handler as claimed in claim 16 , wherein thedriving portion comprises: a motor; a ball screw engaged with a shaft ofthe motor; a ball nut engaged with the ball screw for linearly movingalong with the rotational movement of the ball screw; and a connectingmember for connecting the ball nut and the pivoting portion.
 19. Therambus handler as claimed in claim 11 , wherein the test sockets haveconnection pin arrangements for testing BGA or CSP type semiconductordevices.
 20. The rambus handler as claimed in claim 11 , wherein thetest sockets have connection pin arrangement for testing TSOP typesemiconductor devices, and nonconductive pressing members formed on thelower end of the contact picker assembly for pressing electrodes of theTSOP semiconductor devices to the connection pins of the test socketswhen the TSOP semiconductor devices are connected in the test sockets.21. The rambus handler as claimed in claim 11 , wherein the test chambercomprises: picking position guiding means for guiding the vacuum pads ofthe contact picker assembly to accurate positions in the devicereceiving holes when the contact picker assembly picks the semiconductordevices; de-elevation guiding means for guiding the contact pickerassembly when the contact picker assembly de-elevates to connect thesemiconductor devices to the test sockets; and connecting guiding meansfor guiding the vacuum pads of the contact picker assembly to accuratepositions in the test sockets when the contact picker assembly connectsthe semiconductor device to the test sockets.
 22. The rambus handler asclaimed in claim 21 , wherein the picking position guiding meanscomprises: first and second slope guiding portions correspondinglyformed on left and right sides of the vacuum pads and on both sides ofthe device receiving holes, for guiding an X-directional movement of thevacuum pads in the device receiving holes; and first and second hardstop contacting portions of a predetermined radius of curvature,correspondingly formed on front and rear sides of the vacuum pads and onboth sides of the device receiving holes, for guiding an Y-directionalmovement of the vacuum pads in the device receiving holes.
 23. Therambus handler as claimed in claim 21 , wherein the de-elevation guidingmeans comprises: a multiple pairs of contact guiding pins integrallyformed on the contact picker assembly; and a contact guiding platedisposed on an upper portion of the test head, the contact guiding platehaving a contact guiding pin holes corresponding to the contact guidingpins.
 24. The rambus handler as claimed in claim 21 , wherein theconnection guiding means comprises: third slope guiding portions formedon both side walls of the test socket s corresponding to the first slopeguiding portions of the vacuum pads, for guiding an X-directionalmovement of the vacuum pads; and third hard stop contacting portionsformed on both sides of the test sockets corresponding to the first hardstop contacting portions of the vacuum pads, for guiding anY-directional movement of the vacuum pads.
 25. The rambus handler asclaimed in claim 1 , wherein the device sorting portion comprises: aboat conveying shaft for conveying the boat forward and backward(Y-direction), and stopping the boat at a device adsorbing position; aplurality of single-axis robots for picking the semiconductor devicesfrom the boat with the single-row displaceable hands, and positioningthe semiconductor devices in predetermined areas of the moving buffersaccording to the test results; and two moving buffers for carrying thesemiconductor devices from the boat to the device unloading portion. 26.The rambus handler as claimed in claim 1 , wherein the device unloadingportion comprises a double-axis unloading robot having a pickup handattached to a plurality of pickup cylinders.